Astigmatism Contact Lenses
Astigmatism is a common eye condition in Singapore that is usually present from birth. Having a small degree of astigmatism is normal, but it can be worsened by prolonged usage of digital devices during near-work activities such as reading or typing. This sustained close proximity to screens can strain our eyes, contributing to the development of myopia and astigmatism.
While eyeglasses remain the most affordable method to correct astigmatism, there is a preference for the ease and flexibility offered by contact lenses. With the latest in optical wear technology, users can choose high-performance toric contact lenses that provide greater comfort and visual clarity.
What is Astigmatism?
Astigmatism is the ophthalmological term for a type of refractive error caused by an irregularly shaped cornea. Instead of being shaped like a sphere, an eye with astigmatism is more egg-or oval-shaped. This uneven curvature results in distorted vision, causing light rays to scatter when they enter the eye instead of focusing them onto a single point on the retina. As a result, the refractive error causes blurred vision at all distances, especially at night or in low light.
What Are Toric Contact Lenses?
Toric contact lenses are specialised contact lenses designed to correct astigmatism. Unlike standard contact lenses, toric lenses have a unique shape and design that help them maintain the correct position on your eye for clearer vision and more comfortable wear.
How Do Toric Contact Lenses Work?
Standard contact lenses are made for a spherical cornea, which is curved like a ball, whereas toric lenses are specially manufactured for an astigmatic cornea. Their name ‘toric’ describes the shape of the lenses that are curved like a torus (or more recognisably, a doughnut).
Toric lenses are engineered to have two distinct powers across two different axes. This means each lens has two different prescription strengths on the vertical and horizontal planes to accommodate the irregular curvature of the eye. To maintain this alignment, the lenses have sophisticated design elements to stabilise the lens as your eye blinks and moves.
Types of Astigmatism Contact Lenses
Toric lenses are not all made the same, as they are categorised by their material and their wearing and replacement schedule. Understanding these differences is important when choosing the right lenses for clear and stable vision.
Material and Rigidity
The material of a toric lens determines how comfortable it feels, the degree of oxygen permeability, and how effectively it corrects the irregular curvature of astigmatism:
Soft Toric Lenses
These lenses are made from silicone hydrogel, which is more oxygen-permeable than older hydrogel materials. Soft toric lenses are designed for comfort, making them easier to conform to the shape of your eye.
Soft lenses rely on stabilisation features to prevent rotation when worn. The soft, flexible nature of soft toric lenses makes them suitable for people with mild to moderate astigmatism and first-time contact lens wearers.
Rigid Gas Permeable (RGP) Toric Lenses
These lenses are made of durable, oxygen-permeable plastic. Unlike soft lenses, RGPs do not conform to fit the shape of your eye. RGP lenses work by creating a thin layer of tears between the rigid lens and your cornea. This layer of tears forms a uniform surface that helps reduce the blurred vision associated with astigmatism. As a result, vision is generally more stable and precise.
RGP toric lenses are suitable if you have more severe or irregular astigmatism that cannot be corrected with soft lenses.
Hybrid Toric Lenses
These lenses use a rigid RGP centre surrounded by a soft hydrogel skirt designed for wearability. Hybrid lenses are suitable for patients who need the visual clarity of an RGP lens but cannot tolerate the discomfort of adapting to it.
How To Choose Contact Lenses for Astigmatism
Choosing the correct type of contact lenses can feel a little confusing, but a qualified optometrist and eyecare specialist like Phillips D Izaac will guide you through the process. They provide professional assistance in selecting the type of toric lenses most suitable for your eyes:
- Schedule a professional diagnosis to determine your exact degree of astigmatism
- Familiarise yourself with the different types and traits of rigid gas permeable (RGP) lenses, hybrid lenses, or soft lenses.
- Factor in your daily habits when considering which type of lenses best fit your lifestyle.
It might take more time to be fitted for specialised toric contact lenses than for standard contact lenses, so you need to anticipate a longer eye exam. A thorough examination and complete fitting are required, regardless of your selected lens type, to ensure the lens is aligned on your eye and achieves rotational stability.
Do not forget to consider the cost of the lenses. Toric contacts are usually more expensive than other types of contacts because their manufacturing process is more complex than standard lenses.
Clear Vision Begins with Personalised Eye Consultations
Are you looking for toric contact lenses or other types of specialised lenses prescribed by an optometrist in Singapore? At Philip D. Izaac, we are committed to providing personalised, detailed consultations for the correction and management of astigmatism and myopia. Contact us today to book an appointment.